P0A33 — Drive Motor "B" Temperature Sensor Circuit High

OBD2 code P0A33 flags a problem with the sensor and actuator circuits (drive motor "B" temperature sensor circuit high). The car is usually drivable while you plan the repair. Common culprits: poor ground connection, open or shorted wiring in the circuit, corroded, loose or damaged connector.

powertrain (engine/transmission)

Is it safe to drive?

Short-term driving is OK In most cases the car remains drivable, possibly with reduced performance or a disabled auxiliary system. If symptoms include stalling, no-start or brake/steering warnings, treat it as urgent.

How to diagnose with an OBD scanner

Read the code and freeze frame Connect an OBD2 scanner, confirm P0A33 is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
Check for companion codes and TSBs Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many P0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
Inspect wiring and connectors Visually inspect the wiring harness and connectors related to the drive motor "B" temperature sensor for damage, corrosion, chafing or poor contact.
Subsystem check With the drive motor "B" temperature sensor disconnected, measure signal voltage at the harness connector: a high reading with the component unplugged indicates a short to power in the harness; if it drops to normal, the component itself is faulty.
Subsystem check Measure reference voltage, ground and signal continuity at the component connector.
Subsystem check Wiggle-test the harness while watching the signal in live data — dropouts reveal broken wires.
Verify the repair Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P0A33 does not return.

Approximate repair cost

Repair cost depends on which component actually failed. Typical scenarios for P0A33 (parts and labor, USD, independent shop rates): Replace the faulty sensor or actuator: $150–$500; Repair wiring or connectors: $80–$250; Control module repair: $300–$1,000. Overall, fixing P0A33 usually costs between $80 and $1,000. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.

Common questions

What are the symptoms of P0A33?

Drivers most often notice: Check Engine Light on, increased fuel consumption in some cases, the affected system operates intermittently or not at all, possible limp mode depending on the affected component.

Is it safe to drive with P0A33?

In most cases the car remains drivable, possibly with reduced performance or a disabled auxiliary system. If symptoms include stalling, no-start or brake/steering warnings, treat it as urgent.

What is the most common cause of P0A33?

The most common causes are: poor ground connection, open or shorted wiring in the circuit, corroded, loose or damaged connector.

How do I diagnose P0A33 myself?

Start with a scan: confirm P0A33, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the drive motor "B" temperature sensor, and verify the suspect component against live data before buying parts.

Will P0A33 clear itself?

Sometimes P0A33 clears after a few drive cycles if the fault was intermittent — for example a loose connector or a tank of bad fuel. The underlying cause usually remains, so the code tends to return. Clear it once; if it comes back, diagnose rather than erase it repeatedly.

When your scan tool displays P0A33, the vehicle's control unit has identified that a specific sensor circuit is reporting voltage outside its acceptable operating range. P0A33 stands for "Drive Motor 'B' Temperature Sensor Circuit High," a powertrain-related fault code that specifically targets the temperature monitoring system for the secondary drive motor in hybrid and plug-in hybrid vehicles. The PCM or hybrid control module sets this code when it detects that the sensor's voltage signal has climbed above the upper threshold it expects to see during normal operation.

In practice, a "circuit high" condition means the voltage on the sensor's signal line has risen to approximately battery voltage levels rather than the lower signal range the module anticipates. This voltage spike typically originates from one of three root causes: the signal wire accidentally touching a power source, the ground reference for the sensor opening up and preventing proper circuit completion, or the sensor itself internally failing in a way that pulls the signal high. The control module does not set P0A33 based on a single anomalous reading. It requires the fault condition to persist or recur under specific driving circumstances before illuminating the check engine light, which is why capturing the associated freeze frame data is so valuable for diagnosis.

Symptoms of P0A33

The most obvious symptom is illumination of the check engine light on your dashboard. Beyond that warning lamp, you may notice the hybrid system behaving inconsistently or the affected drive motor failing to engage at all during electric-only operation. Some vehicles respond by entering a reduced-power limp mode to protect drivetrain components until the fault is addressed. Fuel economy may also suffer as the system compensates for the thermal sensor malfunction, forcing the engine to run more frequently than it would under normal hybrid operation.

Common Causes of P0A33

The drive motor "B" temperature sensor itself is often the culprit, with internal failure pulling the signal voltage high. An open ground return path at the sensor prevents proper circuit operation and produces the same high-voltage reading at the module. Wiring problems rank among the most frequent causes, including chafed insulation allowing the signal wire to contact battery positive voltage. Corroded, loose, or physically damaged connectors interrupt proper electrical contact. A blown fuse protecting the sensor circuit will also trigger this code in some vehicle designs. Control module output driver failures, while less common, can produce false high-voltage indications on multiple sensor circuits simultaneously.

How to Diagnose P0A33

Begin by connecting a professional-grade OBD2 scanner and confirming P0A33 is currently stored or pending, then record all available freeze frame data including engine load, RPM, vehicle speed, and coolant temperature at the moment the fault occurred. This information guides your testing by reproducing the exact conditions under which the module first detected the problem. Check for any additional diagnostic trouble codes present alongside P0A33, as related codes often point toward the underlying system at fault. Review manufacturer technical service bulletins using your vehicle's VIN on the automaker's website or NHTSA database, since many sensor-related codes have documented factory fixes or calibration updates.

Perform a thorough visual inspection of the wiring harness and connectors serving the drive motor "B" temperature sensor, looking for damaged wires, corroded pins, bent contacts, or evidence of moisture intrusion. With the sensor connector unplugged, measure voltage at the harness side signal pin using a digital multimeter: a reading near battery voltage confirms a short-to-power condition in the wiring itself, while a normal low-level reading indicates the sensor has failed internally. Verify that the control module is providing the correct reference voltage and solid ground connection at the sensor circuit. Finally, perform a wiggle test on the harness while monitoring live data, watching for signal dropout or fluctuation that reveals intermittent wire breaks.

Repair Options and Costs

Sensor or actuator replacement typically costs between $150 and $500 for parts and labor. Wiring harness repair or connector replacement generally runs $80 to $250 depending on accessibility and extent of damage. If diagnostics point toward the control module itself, expect to pay $300 to $1,000 for module repair or replacement including programming.

Total Repair Cost Summary

The total cost to resolve P0A33 falls anywhere from $80 to $1,000 depending on which component is actually at fault. The majority of cases involve either a faulty temperature sensor or damaged wiring, both relatively straightforward repairs. Control module issues represent the most expensive scenario but occur far less frequently. Spending time on methodical diagnosis before purchasing parts almost always saves money, since the priciest repair is rarely the first one to investigate.

Can You Drive with P0A33?

Most vehicles remain operational when P0A33 is active, though you may experience reduced hybrid performance, intermittent electric motor operation, or slightly elevated fuel consumption. The car will not typically leave you stranded. However, if the malfunction triggers limp mode, causes stalling, or produces warnings related to braking or power steering systems, treat the situation as urgent and seek diagnosis promptly.